Monitoring the wear on mechanical hardware can be important in a range of different circumstances. For instance monitoring for wear on aircraft, such as drive shafts of the main gear box of helicopters and the rear rotor of helicopters should be conducted on a routine basis for safe and reliable operation.
In the case of helicopter drive shafts, silver plating is present over an inner high tensile steel core. Conventional testing techniques usually involve a simple visual inspection of the silver plating surface to detect where the silver plating has been removed. One of the difficulties of the conventional approach is that it can be difficult to differentiate between sections, particular small sections, where the silver plating has been removed and the inner steel core. This can create reliability issues in the test method.
Notwithstanding this difficulty, it is recognised that signs of wear and tear on the silver plating of helicopter drive shafts can occur prior to malfunction and possible catastrophic failure of the drive shaft.
The present invention is directed to an alternative technique for identifying the wear regions of the outer portion or coating of mechanical hardware.